The Diabetes Prevention Program (DPP) demonstrated that weight loss achieved through changes in physical activity and diet was more effective at preventing type 2 diabetes mellitus (DM) than a pharmacologic intervention; however, translation of the DPP into the community has lagged for multiple reasons. The Healthy Living Partnership to Prevent Diabetes (HELP PD) Trial (funded Sept. 2006 - Aug. 2011) is a translational study of 300 overweight or obese persons with pre-diabetes randomized to usual care (UC) or a group-based lifestyle intervention (LI) facilitated by community health workers (CHWs) and supported by staff of a Diabetes Care Center. To date, recruitment, retention, intervention, and assessment have been excellent and 6-month weight loss is averaging 6.4%. Since Aug. 2007, we have enrolled 258 participants, and we plan to enroll 42 more by Mar. 2009. Follow-up was funded for a uniform 2 years; hence, the earliest-enrolled participants (enrolled in Aug. 2007) will complete follow-up for HELP PD in Aug. 2009. The primary goal of this competitive renewal is to test the long-term glucose lowering effects of the HELP PD intervention by randomizing the LI group to continued group maintenance (GM) or self-directed maintenance (SM) and following the UC group for additional comparison purposes. Additional funding, partially overlapping with current funding, is requested to re-enroll participants as they complete initial follow-up, thus giving those who continue GM a seamless intervention and the opportunity to begin new follow-up visits 6 months after the final HELP PD visit for an additional 36-48 months. We will test the value of long-term GM versus an initial 2-year intervention followed by SM, with the added value of a true comparison group (UC) to define biological effects. Secondary outcomes include other biologic parameters (insulin, lipids, blood pressure, weight, waist), behaviors, and cost-effectiveness. We will have good power to evaluate the effectiveness of the HELP PD approach in maintaining glucose and weight change, and other biologic effects. Notably, follow-up in DPP was, on average, 3.2 years. If this application is approved, follow-up will be extended from 24 to 60-72 months for this cohort, and we will be able to transition into extended maintenance without a gap in intervention; hence, we are well positioned to test the proposed hypotheses. Demonstrating the longer term effectiveness of HELP PD represents a key step in establishing the value of this approach to translation of DM prevention into the community. This crucial evidence will be used to support reimbursement policy for DM prevention, dissemination of the HELP PD CHW approach and generalization to other behaviorally influenced chronic diseases.